Rotary earth-boring bits useful for oil and gas exploration and production have evolved considerably since the bi-cone bit developed by Howard R. Hughes, Sr., which had two rotatable cone-shaped cutting assemblies. Today, there are rotary bits with fixed or non-rotating blades with polycrystalline diamond cutters (PDC) mounted thereon. There are also hybrid bits combining fixed-blade cutting elements and rotating cutting elements. Most, but not all hybrid bits are modular in construction, in that the rotatable or rolling cutter elements are separate components coupled to the bit body by welding or other type of fastening.
The embodiments disclosed and taught herein are directed to an improved modular hybrid drill bit having at least one rolling cutter assembly mechanically fastened to the bit body.